The Bilger Quarry was originally owned by the Oakland Paving Company which mined Franciscan quartz Diorite in the quarry, crushed it and then shipped the finished product out on the railway that crossed Broadway and 42nd Street on to the depot at 41st Street and Shafter Street. Later the quarry was operated by Blake & Bilger Company.

The former quarry is now filled with water from the Rockridge branch of the Glen Echo Creek and is owned by the Claremont Country Club, which uses the water for irrigating its golf course. Over the years, there has been at least one drowning. On March 31, 1955, 7 year old Gary Schaffer and two friends climbed over a broken part of the fence and went 'exploring'. Gary slipped from a rope, fell into the water, and drowned. It took divers all night to find his body, caught in a tangle of branches. 3

Some believe that between 1873 and 1923 a 3' gauge steam railroad ran between the Bilger Quarry and the rock crushing plant. After the quarry was abandoned in 1923 houses were constructed on the former railway. Others believe that the right of way was acquired for the Key System, and was never used by the quarry.

"Blake and Bilger Company's Quarry (formerly the Oakland Paving Company's Quarry); F. W. Bilger, secretary and treasurer, Central Bank Building, Fourteenth and Broadway, Oakland. Located on McAdam street, just off Broadway. It was opened about 1870, and has been operated almost constantly since. It is the largest quarry in Alameda County. The rock is typical 'blue rock,' as termed by the trade, and is a metamorphosed sandstone, with lime carbonate in seams. It is used for macadam, concrete, and gutter rock. Two Gates crushers handle all the rock. Two steam percussion drills are in operation. From 60 to 80 quarrymen are employed." 2